//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

package com.tongle.frs.common.util.security;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.io.ByteArrayOutputStream;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;

public class RSAUtil {
  public static final String KEY_ALGORITHM = "RSA";
  public static final String SIGNATURE_ALGORITHM = "MD5withRSA";
  private static final String PUBLIC_KEY = "RSAPublicKey";
  private static final String PRIVATE_KEY = "RSAPrivateKey";
  private static final int MAX_ENCRYPT_BLOCK = 117;
  private static final int MAX_DECRYPT_BLOCK = 128;

  public RSAUtil() {
  }

  public static Map<String, Object> genKeyPair() throws Exception {
    KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA");
    keyPairGen.initialize(1024);
    KeyPair keyPair = keyPairGen.generateKeyPair();
    RSAPublicKey publicKey = (RSAPublicKey)keyPair.getPublic();
    RSAPrivateKey privateKey = (RSAPrivateKey)keyPair.getPrivate();
    HashMap keyMap = new HashMap(2);
    keyMap.put("RSAPublicKey", publicKey);
    keyMap.put("RSAPrivateKey", privateKey);
    return keyMap;
  }

  public static String sign(byte[] data, String privateKey) throws Exception {
    byte[] keyBytes = Base64.decodeBase64(privateKey);
    PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PrivateKey privateK = keyFactory.generatePrivate(pkcs8KeySpec);
    Signature signature = Signature.getInstance("MD5withRSA");
    signature.initSign(privateK);
    signature.update(data);
    return Base64.encodeBase64String(signature.sign());
  }

  public static boolean verify(byte[] data, String publicKey, String sign) throws Exception {
    byte[] keyBytes = Base64.decodeBase64(publicKey);
    X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PublicKey publicK = keyFactory.generatePublic(keySpec);
    Signature signature = Signature.getInstance("MD5withRSA");
    signature.initVerify(publicK);
    signature.update(data);
    return signature.verify(Base64.decodeBase64(sign));
  }

  public static byte[] decryptByPrivateKey(byte[] encryptedData, String privateKey) throws Exception {
    byte[] keyBytes = Base64.decodeBase64(privateKey);
    PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PrivateKey privateK = keyFactory.generatePrivate(pkcs8KeySpec);
    Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
    cipher.init(2, privateK);
    int inputLen = encryptedData.length;
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    int offSet = 0;

    for(int i = 0; inputLen - offSet > 0; offSet = i * 128) {
      byte[] cache;
      if(inputLen - offSet > 128) {
        cache = cipher.doFinal(encryptedData, offSet, 128);
      } else {
        cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
      }

      out.write(cache, 0, cache.length);
      ++i;
    }

    byte[] decryptedData = out.toByteArray();
    out.close();
    return decryptedData;
  }

  public static byte[] decryptByPublicKey(byte[] encryptedData, String publicKey) throws Exception {
    byte[] keyBytes = Base64.decodeBase64(publicKey);
    X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PublicKey publicK = keyFactory.generatePublic(x509KeySpec);
    Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
    cipher.init(2, publicK);
    int inputLen = encryptedData.length;
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    int offSet = 0;

    for(int i = 0; inputLen - offSet > 0; offSet = i * 128) {
      byte[] cache;
      if(inputLen - offSet > 128) {
        cache = cipher.doFinal(encryptedData, offSet, 128);
      } else {
        cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet);
      }

      out.write(cache, 0, cache.length);
      ++i;
    }

    byte[] decryptedData = out.toByteArray();
    out.close();
    return decryptedData;
  }

  public static byte[] encryptByPublicKey(byte[] data, String publicKey) throws Exception {
    byte[] keyBytes = Base64.decodeBase64(publicKey);
    X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PublicKey publicK = keyFactory.generatePublic(x509KeySpec);
    Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
    cipher.init(1, publicK);
    int inputLen = data.length;
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    int offSet = 0;

    for(int i = 0; inputLen - offSet > 0; offSet = i * 117) {
      byte[] cache;
      if(inputLen - offSet > 117) {
        cache = cipher.doFinal(data, offSet, 117);
      } else {
        cache = cipher.doFinal(data, offSet, inputLen - offSet);
      }

      out.write(cache, 0, cache.length);
      ++i;
    }

    byte[] encryptedData = out.toByteArray();
    out.close();
    return encryptedData;
  }

  public static byte[] encryptByPrivateKey(byte[] data, String privateKey) throws Exception {
    byte[] keyBytes = Base64.decodeBase64(privateKey);
    PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    PrivateKey privateK = keyFactory.generatePrivate(pkcs8KeySpec);
    Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm());
    cipher.init(1, privateK);
    int inputLen = data.length;
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    int offSet = 0;

    for(int i = 0; inputLen - offSet > 0; offSet = i * 117) {
      byte[] cache;
      if(inputLen - offSet > 117) {
        cache = cipher.doFinal(data, offSet, 117);
      } else {
        cache = cipher.doFinal(data, offSet, inputLen - offSet);
      }

      out.write(cache, 0, cache.length);
      ++i;
    }

    byte[] encryptedData = out.toByteArray();
    out.close();
    return encryptedData;
  }

  public static String getPrivateKey(Map<String, Object> keyMap) throws Exception {
    Key key = (Key)keyMap.get("RSAPrivateKey");
    return Base64.encodeBase64String(key.getEncoded());
  }

  public static String getPublicKey(Map<String, Object> keyMap) throws Exception {
    Key key = (Key)keyMap.get("RSAPublicKey");
    return Base64.encodeBase64String(key.getEncoded());
  }
}
